Manufacture of waterproof articles from fibrous materials.



citizen of the ,wet way with various chemical agents.

- processes at least, the fact that the weight liability of breakage.

- naturally in them, in

fibers of which UNITED sTA Es PATENT OFFICE. ISAIAH aosrars, or LQOiiPQRT. ew YORK.

MANUFACTURE OF WATERPROOF ARTICLES FROM FIIBRQUS MATERIALS.

N 0. 921,001. Specification of Letters Patent. Patented May 11, 19.08.

Application filed H38? 26, 19%. Serial No. 185,130.

To all whom it may concern:

Be it known this res ect a good deal like the feathers of that I, ISAIAH L. ROBERTS, a i bird's. lhe treatment with the water-repel- United States, residing at I lent substance can be efiected in various ways Lockport, .in the, county of Niagara and i and with variousmaterials, but the organic State of New York, have invented certain oils appear to give the best results. For exnewand useful Improvements in the Manuample, in makin waterproof cotton cloth, facture of Waterproof Articles from Fibrous the'oil may be b own or atomized on to Materials, of which the following is a specifi- I the dry cotton fibers before spinning. Or, if cat1on. Wax is used, the same may be pulverized or My invention relates to the manufacture i melted and then blown in a fine spray on to of waterproof articles, for example tubes, the cotton. In the case of wood-pulp, strawrods, Vessels, plates, sheets, etc, composed of fibrous material such aswood, pulp, strawboard, paper, cotton and other cellulose products, and has for its chief object to provide a simple,,cheap, and withal thorou hly effective process for rendering such articles non-absorptive or waterproof.

Heretofore it has been customary toimpregnate the articles, or fill the pores thereof, with water roofing material, or to coat the surface of t e article with suitable impervious material, or to treat. the article in the put into 'the pulping machines and thoroughly mixed with the fibers. This method applies both to original pulping or to the repu ping of pulp-board, strawboard, etc. In the case of articles made wholly or in part of repulped printed paper, I have found the oil. of the printers ink is usually sufficient for the purpose desired; but if not, additional waterrepellent oil or wax may be used. From the material treated as above or in an equivalent manner, the cloth, vessels, or other articles or roducts are made by the usual methods, and are then heated. The heating is preferably efl'ected 'in a closed or partially closed chamber or oven, and is carried to a temperature above that of boiling water to a point sufficient to cause the oil or wax to be thoroughly incorporated with the fibers. The temperature requiredfor the purpose depen s upon the nature of the material and the article, but in no case have I found-it necessary to go above 400 F., and in many cases a temperature as low as 240 F. has been found suflicient. The length of time during which the heating should be maintained also varies, but in general two to eighteen hours will be found sufficient. At the lower temperature itis necessary to heat the article lon er than at the hi her temperature, and simi arly thick-walled articles need and at the same time o li hter weight, 5 longer heating at any given temperature than stronger texture and less liab' 'ty to break, those whose walls are thinner. In order to without increasing the weight thereof or the g' be sure of the results, the heating must be i carried on for a period and at a temperature 2 sufficient to partially decompose the fibers of the article and to effect a combination of the However successful for the u ose the prior methods may have proved :ll those with which I am familiar, particularly the methods just referred to, possess certain drawbacks. Chief among these drawbacks are the matter of. expense and, in some of the of the article'is largely increased by the considerable quantit of impregnating or coating-material emp oyed. Furthermore, such articles when coated or im regnated have little or'none of their natura resiliency and as a result are liable tobreakage under strains that otherwise might cause merel .a temporary distortion. I have therefhre been led to devise my present invention, by which I am able 'to produce fibrous articles which are thoroughly wate roof at low cost,

The most im ortant feature of my inveng tion'resides in t e discovery that on heating an article composed of fibrous cellulose the l oils, gums or waxes therewith. At temperahave some water repellent ltures between the boiling point of water and substance or substances, such as oil or parafabout 400 F. the heating has, the effect of fin, well distributed on and among them or strengthening the articles, but at higher temminute or attenuated I peratures they are'weakened.

While the use of oil or other \\-':'iter-rcpelquantities so minute in fact, as not to be pali l lent substance is believed to be necessary for pable tothe touch or visible to the eye, the article will repel water completely, acting in i the best results, I have found that simple llil heating of articles made of wood-pulp, ragetc., will give them water repellent 1 pul The water in the vessel H soon begins to vaporize, and the steam therefrom displaces qua 'ties to a marked degree,sullic1ent, at l the air, which is allowed to escape through a least, to serve many purposes where substanl cock J, convenientl located.

lower p ate may be placed a vessel l1, con- I When the de- 4. The herein described method of manu- I facturing waterproof articles, which consists tially waterproof articles are desired, as for sired temperature ias been reached, as can 55 example reoe tacles for the storage or shipbe determined from a thermometer, as K, exment of mere andise. Such articles, made of tending into the oven at any convenient material of the kind referred to and heated to point, the heat is maintained at about that. a temperature of from 240 to 400 F. for degree for the time desired, after which the from two to eighteen hours or longer, (the articles are removed and allowed to cool. Of 60 higher the temperature the shorter the time, course in the case of treatment without water and vice versa), will maintain their contents the vessel H is omitted or merely left empty, dry for a long time even under adverse conas desired. ditions of the atmosphere or weather. Straw- It is to be understood that the apparatus board, however, does not do so well with herein shown is not an essential part of my 65 simple heating, but should have the treatinvention, which being a process, is not conment with water-repellent oil or wax, as fined to any particular type or kind of appaherein described. ratus for racticing it.

If water vapor is added to the atmosphere What claim is: w in the oven in which the articles are heated it 1.' The herein described method of mauu- 7c will in some cases improve the results. For facturing waterproof articles, which consists this purpose an openvessel containing asmall in forming an article of pulped cellulose or quantity of water may be placed in the oven, woody material, and heating the article .to a or steam may be injected into the oven. temperature suiliciently high and for a time The use of water vapor in the atmosphere of sufiiciently long, as described, to render the T the oven does not result in making the artiarticle substantially waterproof. cles moist or damp since the temperature is 2. The herein described method of manuabove the condensing point of water. I facturing waterproof articles, which consists A convenient type of heating apparatus in forming an article of pulped cellulose or for use in practicing my invention is 'illus-' woody fibers treated with a water-repelling $0 trated in the annexed drawing. The figure substance, and heating the article for a suilithere given shows the heating oven in vercient time and at a temperature suiliciently tical section. high, as described, to render the article water- The oven A, having heat-insulating walls, proof. contains a coiled heating pipe B, provided 3. The herein described method of manu- 5 with suitable valves C, 1), for controlling the facturing waterproof articles, which consists flow of the steam or other heating medium in forming an article of ulped cellulose or therethrough. Close above the heating coil, woody material, and heating the article to a which is located at the bottom of the oven, temperature above the boiling point of water are two erforated iron plates, E, F. On the l for approximately two hours or longer. 90

taining water. 011 the upper plate are placed the articles to be treated, which are preferz, in forming an article of pulped cellulose or ably disposed so as to pergnit the atmosphere i woody material, and heating the article to a of the oven to readily reach all parts. The l temperature of from 240 to 400 F. for ap- "articles are introduced through an opening E proximately two hours or longer.

in the side of the oven, which is then closed i ISAIAH L. ROBERTS.

tightly by a closure or door I. g The oven being charged, the steam or other 50 heating medium is let into the heating coil. i

W itnesses:

M. LAWSON DYER, S. S. DUNHAM. 

